/* Copyright (c) 2016 PaddlePaddle Authors. All Rights Reserve.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License. */

#include "MathFunctions.h"
#include "hl_matrix_apply.cuh"
#include "hl_matrix_ops.cuh"
#include "paddle/utils/DynamicLoader.h"

namespace dynload {

std::once_flag lapack_dso_flag;
void* lapack_dso_handle = nullptr;

/**
 * The following macro definition can generate structs
 * (for each function) to dynamic load lapack routine
 * via operator overloading.
 *
 * note: default dynamic linked libs
 */

// The argument for stringizing operator is not macro-expanded first.
// We have to use two levels of macro to do the expansion.
// See https://gcc.gnu.org/onlinedocs/cpp/Stringizing.html
#define STR(x) #x

// clang-format off
#ifndef LAPACK_FOUND
#define DYNAMIC_LOAD_LAPACK_WRAP(__name)                                       \
  struct DynLoad__##__name {                                                   \
    template <typename... Args>                                                \
    auto operator()(Args... args) -> decltype(__name(args...)) {               \
      using lapack_func = decltype(__name(args...)) (*)(Args...);              \
      std::call_once(lapack_dso_flag, GetLapackDsoHandle, &lapack_dso_handle); \
      void* p_##__name = dlsym(lapack_dso_handle, STR(__name));                \
      CHECK(p_##__name) << "Cannot find symbol " << STR(__name)                \
                        << " in liblapack.so";                                 \
      return reinterpret_cast<lapack_func>(p_##__name)(args...);               \
    }                                                                          \
  } __name;  // struct DynLoad__##__name
#else
#define DYNAMIC_LOAD_LAPACK_WRAP(__name)                                       \
  struct DynLoad__##__name {                                                   \
    template <typename... Args>                                                \
    auto operator()(Args... args) -> decltype(__name(args...)) {               \
      return __name(args...);                                                  \
    }                                                                          \
  } __name;  // struct DynLoad__##__name
#endif

#ifdef PADDLE_USE_ATLAS
  #define  PADDLE_SGETRF  clapack_sgetrf
  #define  PADDLE_DGETRF  clapack_dgetrf
  #define  PADDLE_SGETRI  clapack_sgetri
  #define  PADDLE_DGETRI  clapack_dgetri
#else
  #define  PADDLE_SGETRF  LAPACKE_sgetrf
  #define  PADDLE_DGETRF  LAPACKE_dgetrf
  #define  PADDLE_SGETRI  LAPACKE_sgetri
  #define  PADDLE_DGETRI  LAPACKE_dgetri
#endif

#define LAPACK_ROUTINE_EACH(__macro)       \
  __macro(PADDLE_SGETRF)                   \
  __macro(PADDLE_DGETRF)                   \
  __macro(PADDLE_SGETRI)                   \
  __macro(PADDLE_DGETRI)
// clang-format on

LAPACK_ROUTINE_EACH(DYNAMIC_LOAD_LAPACK_WRAP)

}  // namespace dynload

namespace paddle {

#ifndef PADDLE_USE_EIGEN_FOR_BLAS
template <>
void gemm<float>(const CBLAS_TRANSPOSE transA,
                 const CBLAS_TRANSPOSE transB,
                 const int M,
                 const int N,
                 const int K,
                 const float alpha,
                 const float* A,
                 const int lda,
                 const float* B,
                 const int ldb,
                 const float beta,
                 float* C,
                 const int ldc) {
  cblas_sgemm(CblasRowMajor,
              transA,
              transB,
              M,
              N,
              K,
              alpha,
              A,
              lda,
              B,
              ldb,
              beta,
              C,
              ldc);
}

template <>
void gemm<double>(const CBLAS_TRANSPOSE transA,
                  const CBLAS_TRANSPOSE transB,
                  const int M,
                  const int N,
                  const int K,
                  const double alpha,
                  const double* A,
                  const int lda,
                  const double* B,
                  const int ldb,
                  const double beta,
                  double* C,
                  const int ldc) {
  cblas_dgemm(CblasRowMajor,
              transA,
              transB,
              M,
              N,
              K,
              alpha,
              A,
              lda,
              B,
              ldb,
              beta,
              C,
              ldc);
}
#endif

template <>
int getrf<float>(const CBLAS_ORDER order,
                 const int M,
                 const int N,
                 float* A,
                 const int lda,
                 int* ipiv) {
  return dynload::PADDLE_SGETRF(order, M, N, A, lda, ipiv);
}

template <>
int getrf<double>(const CBLAS_ORDER order,
                  const int M,
                  const int N,
                  double* A,
                  const int lda,
                  int* ipiv) {
  return dynload::PADDLE_DGETRF(order, M, N, A, lda, ipiv);
}

template <>
int getri<float>(const CBLAS_ORDER order,
                 const int N,
                 float* A,
                 const int lda,
                 const int* ipiv) {
  return dynload::PADDLE_SGETRI(order, N, A, lda, ipiv);
}

template <>
int getri<double>(const CBLAS_ORDER order,
                  const int N,
                  double* A,
                  const int lda,
                  const int* ipiv) {
  return dynload::PADDLE_DGETRI(order, N, A, lda, ipiv);
}

#ifndef PADDLE_USE_EIGEN_FOR_BLAS
template <>
void axpy<float>(const int n, const float alpha, const float* x, float* y) {
  cblas_saxpy(n, alpha, x, 1, y, 1);
}

template <>
void axpy<double>(const int n, const double alpha, const double* x, double* y) {
  cblas_daxpy(n, alpha, x, 1, y, 1);
}

template <>
float dotProduct<float>(const int n, const float* x, const float* y) {
  return cblas_sdot(n, x, 1, y, 1);
}

template <>
double dotProduct<double>(const int n, const double* x, const double* y) {
  return cblas_ddot(n, x, 1, y, 1);
}
#endif

#if defined(PADDLE_USE_MKLML)

template <>
void vExp<float>(const int n, const float* a, float* r) {
  vsExp(n, a, r);
}

template <>
void vExp<double>(const int n, const double* a, double* r) {
  vdExp(n, a, r);
}

template <>
void vPow<float>(const int n, const float* a, const float b, float* r) {
  vsPowx(n, a, b, r);
}

template <>
void vPow<double>(const int n, const double* a, const double b, double* r) {
  vdPowx(n, a, b, r);
}

template <>
void vLog<float>(const int n, const float* a, float* r) {
  vsLn(n, a, r);
}

template <>
void vLog<double>(const int n, const double* a, double* r) {
  vdLn(n, a, r);
}

template <>
void vAdd<float>(const int n, const float* a, const float* b, float* r) {
  vsAdd(n, a, b, r);
}

template <>
void vAdd<double>(const int n, const double* a, const double* b, double* r) {
  vdAdd(n, a, b, r);
}
#else

DEFINE_MATRIX_BINARY_OP(vExp, b = std::exp(a));
template <class T>
void vExp(const int n, const T* a, T* r) {
  hl_cpu_apply_binary_op<T, binary::vExp<T>, 0, 0>(
      binary::vExp<T>(), const_cast<T*>(a), r, 1, n, n, n);
}

DEFINE_MATRIX_BINARY_OP(vLog, b = std::log(a));
template <class T>
void vLog(const int n, const T* a, T* r) {
  hl_cpu_apply_binary_op<T, binary::vLog<T>, 0, 0>(
      binary::vLog<T>(), const_cast<T*>(a), r, 1, n, n, n);
}

DEFINE_MATRIX_BINARY_PARAMETER_OP(vPow, ONE_PARAMETER, b = std::pow(a, p));
template <class T>
void vPow(const int n, const T* a, const T b, T* r) {
  hl_cpu_apply_binary_op<T, binary::vPow<T>, 0, 0>(
      binary::vPow<T>(b), const_cast<T*>(a), r, 1, n, n, n);
}

DEFINE_MATRIX_TERNARY_OP(vAdd, c = a + b);
template <class T>
void vAdd(const int n, const T* a, const T* b, T* r) {
  hl_cpu_apply_ternary_op<T, ternary::vAdd<T>, 0, 0>(ternary::vAdd<T>(),
                                                     const_cast<T*>(a),
                                                     const_cast<T*>(b),
                                                     r,
                                                     1,
                                                     n,
                                                     n,
                                                     n,
                                                     n);
}

template void vExp(const int n, const float* a, float* r);
template void vExp(const int n, const double* a, double* r);
template void vLog(const int n, const float* a, float* r);
template void vLog(const int n, const double* a, double* r);
template void vPow(const int n, const float* a, const float b, float* r);
template void vPow(const int n, const double* a, const double b, double* r);
template void vAdd(const int n, const float* a, const float* b, float* r);
template void vAdd(const int n, const double* a, const double* b, double* r);

#endif

DEFINE_MATRIX_BINARY_OP(vInvSqrt, b = 1.0f / std::sqrt(a));
template <class T>
void vInvSqrt(const int n, const T* a, T* r) {
  hl_cpu_apply_binary_op<T, binary::vInvSqrt<T>, 0, 0>(
      binary::vInvSqrt<T>(), const_cast<T*>(a), r, 1, n, n, n);
}

DEFINE_MATRIX_BINARY_OP(vLog1p, b = std::log(1.0f + a));
template <class T>
void vLog1p(const int n, const T* a, T* r) {
  hl_cpu_apply_binary_op<T, binary::vLog1p<T>, 0, 0>(
      binary::vLog1p<T>(), const_cast<T*>(a), r, 1, n, n, n);
}

DEFINE_MATRIX_BINARY_OP(vTanh, T tmp = -2.0 * a;
                        tmp = (tmp > EXP_MAX_INPUT) ? EXP_MAX_INPUT : tmp;
                        b = 2.0 / (1.0 + std::exp(tmp)) - 1.0);
template <class T>
void vTanh(const int n, const T* a, T* r) {
  hl_cpu_apply_binary_op<T, binary::vTanh<T>, 0, 0>(
      binary::vTanh<T>(), const_cast<T*>(a), r, 1, n, n, n);
}

template void vInvSqrt(const int n, const double* a, double* r);
template void vInvSqrt(const int n, const float* a, float* r);
template void vLog1p(const int n, const float* a, float* r);
template void vLog1p(const int n, const double* a, double* r);
template void vTanh(const int n, const float* a, float* r);
template void vTanh(const int n, const double* a, double* r);

}  // namespace paddle
